More noise on sound
at Armow Wind hearing
By Liz Dadson
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Acousticians made some more noise about sound in the final week of the Environmental Review Tribunal into the appeal against the Armow Wind development in Kincardine.
Friday afternoon (Jan. 10), Robert O'Neal, an expert acoustician and witness for the approval holder, Samsung Pattern Armow Wind Ontario GP, gave testimony about wind turbine noise.
He said there are two sources of sound in the wind turbines: the mechanical sound from the nacelle; and the aerodynamic noise from the blades. The older design, called "downwind," has been replaced by a newer design, called "upwind."
With the old design, air moves around the tower, said O'Neal. That has been eliminated with the new design.
He described low-frequency noise and infrasound, stating that the human ear can hear noise from 20-20,000 Hertz (Hz). Low-frequency is found at 20-200 Hz, and below 20 Hz is infrasound.
O'Neal said that, at 10 Hz, infrasound would have to be at 97 decibels (dBA) to be audible, but at 100 Hz, low-frequency noise could be heard at 27 dBA.
"This is not unique to wind," he said. "It's pretty much the same everywhere."
Sarah Powell, counsel for the approval holder, asked O'Neal if he had reviewed the transcript by Rick James, acoustician for the appellants, Ken and Sharon Kroeplin.
"Yes, I reviewed it," said O'Neal.
Powell asked O'Neal to comment on some of the findings by James, pertaining to wind turbine noise.
"Wind turbine sound is not that different from other sounds," said O'Neal. "There are some spikes in the sound, but they don't sound like gun shots."
He went on to outline specifics about synchronization and pulsation.
Powell asked him to comment on his research study from 2011, on large wind developments.
O'Neal said that study was three-fold: reviewing the standards in the world today; doing field studies; and comparing that information with the standards and guidelines.
He said that work was peer-reviewed and published. It found that infrasound and low-frequency sound were below audible levels. However, vibration and rattle were within audible levels.
Under cross-examination by Asha James, counsel for the appellants, O'Neal was asked if the modern turbines are not as noisy.
O'Neal qualified that by saying that the older turbines were also smaller. "As turbines get bigger, there is engineering being done to make them quieter."
James said the participants and presenters at the hearing, claim they have been affected by the noise of the turbines.
"I assume that's why we are having this hearing," said O'Neal.
"Have you reviewed anything from the post-turbine witnesses?" asked James.
"No," said O'Neal.
"The post-turbine witnesses are not complaining about old, noisy turbines," said James.
BILL PALMER REFUTES WITNESSES FOR MOE AND APPROVAL HOLDER
Meanwhile, Bill Palmer, local expert on acoustics and public safety, spoke Friday morning (Jan. 10), addressing several respondents and their evidence.
Alexandria Pike, counsel for the approval holder, objected to the extensive presentation by Palmer, in light of the fact that he already gave the same evidence in his own presentation earlier in the hearing.
"I'm clearly aware that I've given my evidence," said Palmer. "I wish to respond to comments and witness statements by the witnesses for the MOE (Ontario Ministry of the Environment) and Samsung Pattern (approval holder)."Tribunal chairperson Maureen Carter-Whitney said Palmer could use his notes for his oral presentation but they would not be entered into evidence.
'Well, then I will be reading nine pages," said Palmer, "and that will take about 45 minutes. I was trying to make things easier by giving you all copies of my presentation."
Pike asked for a five-minute break and all three counsels reviewed Palmer's presentation.
There was not enough time to review the entire thing, said Pike, noting that it is not a clear reply but repeats items already in evidence. "If Mr. Palmer would focus on the highlights and then we can raise objections," she said.
"We did receive your evidence so there's no need to repeat it," said Carter-Whitney.
Palmer cited testimony by Dejan Zivkovic, the MOE's noise expert, and questioned his statement that the temporal characteristics of wind turbines do not contain a repetitive cyclical noise.
"I'm responding to Mr. Zivkovic's statement which is saying that some of Mr. Palmer's comments are not correct," said Palmer. "It's inappropriate of Mr. Zivkovic to say that the noise level is 10 dBA lower if upwind. If you're 3,500 metres from the turbine, the difference is 10 dBA."
Palmer also took issue with comments by Shant Dokouzian, sound expert for the approval holder, and the sound measurements referenced by Dokouzian.
In addition, Palmer had concerns with negative statements by Ben Coulson, sound expert for the approval holder, regarding Palmer's work.
Pike asked Palmer if his work for papers that he presented at wind conferences in Seattle and Rome in 2011, and in Denver in 2013, were in compliance with international standards for noise.
"Yes," said Palmer.
"Does the apparatus used comply with measurement standards?" asked Pike.
"I don't have those standards in front of me," said Palmer.
"Have you advised your peer group if the apparatus used complied with those standards?" asked Pike.
"I describe the response data collection method that was used," said Palmer. "The measurements were taken in the field. The intent was not precise values. The intent was to show the difference between the different sites."
Under cross-examination by Danielle Meuleman, counsel for the MOE director, regarding public safety, Palmer was asked if he had seen the policy for the Hydro One setback for a 500-kV corridor.
Palmer said he had a letter from Hydro One stating the standards and that was later confirmed.
"But you have never seen the content of the technical guidelines," said Meuleman.
"No, but I have requested it," said Palmer.
Regarding blade failure at wind farms, Meuleman said there is nothing built by humans that has not failed at some point.
"Yes, that's why you calculate an actual failure rate," said Palmer.
He said the risks for wind turbines need to be calculated as individual exposure rather than population exposure. For example, the risks at the Bruce Nuclear site are calculated as individual exposure, while the risks at the Pickering site are calculated as population exposure.
"There is an acceptable risk value for everything," said Meuleman.
"I don't want to be the one who says that the car your son was driving had an acceptable brake failure rate," said Palmer. "That isn't an acceptable value."
"There is an acceptable risk value; it's the nature of the business," said Meuleman. "But you think all risks should be mitigated."
"All people are equal," said Palmer. "I would say, how can I mitigate the risk?"
"Despite the cost?" asked Meuleman.
"You should not improve the risk for some people and not for others," said Palmer.
The hearing wrapped up Tuesday. The tribunal must now render a decision.
The appeal, launched Oct. 23 by the Kroeplins, is against the proposed Armow Wind Class 4 wind facility, a 92-turbine, 180-megawatt industrial wind development in Kincardine. It was approved by the director of the MOE through the REA process, Oct. 9.
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Friday, January 17, 2014